Universal Catalytic Converter for Gas & Diesel Engines

Hi,

I randomly came across this page -> http://www.auco-shop.de/prod_kat.html?gclid=COL_mYH43ZYCFQWJ1QodMjJi2g

"Universal catalytic converters" are being offered. Whether they are for gasoline or diesel engines seems irrelevant, but it shouldn't be, because a diesel oxidation catalyst (DOC) functions fundamentally differently from a three-way catalytic converter used in gasoline engines.

What do you think – is it a matter of customer acceptance, or is it already technically feasible?

vwSchrauber wrote:

... "Universal catalytic converters" are being offered, and it seems that whether they are for a gasoline or diesel engine doesn't matter. ...

Exactly that is not mentioned anywhere. I think the author of this somewhat meager page simply swept the diesel catalytic converters under the rug.
Furthermore, I assume that despite the word "universal," there will be hundreds of different types.

Quote:

with lambda sensor connection. -> above and to the right of Kat

That makes me agree with Bertil. After all, how many diesels actually have a lambda sensor (only the very newest ones do).

Okay, please provide the German text you would like me to translate into English. I will only provide the translation.

Thank you, that's exactly what I suspected.
The whole thing smells very much like a loss of approval (ABE) when installing such a catalytic converter, even if it boasts the E-mark .

vwSchrauber wrote:

... The whole thing smells very much like a loss of the ABE (General Operating Permit) when installing such a catalytic converter, even if it boasts an "E" marking

.

Not necessarily, but definitely after a registration.
A certified and emissions-relevant component is being replaced with a different one. This usually requires registration. As a result, the cost advantage of the "universal" option may disappear.

Hello,

Putting aside all the ABE (German vehicle approval) nonsense, what exactly is different about the internal workings of a diesel and a gasoline catalytic converter?

In a diesel engine, only oxidation (of HC and CO) occurs because with an excess of oxygen, reduction (of NOx) simply doesn't work. However, the underlying chemistry is otherwise the same.

Best regards,

Albrecht wrote:

Hello, Putting aside all the ABE (German vehicle approval) nonsense, what exactly is different about the internal workings of a diesel and a gasoline catalytic converter?

Have you ever considered the not-insignificant difference in exhaust gas temperatures?

Since a catalytic converter operates correctly within a relatively narrow temperature range, I can't imagine that a diesel catalytic converter and a gasoline catalytic converter are the same.

Hello,

"This thing works starting from XX °C. I don't see the huge temperature differences with an underbody catalytic converter. What changes in the reactions of the exhaust components? The chemistry remains the same as described above. Of course, it goes without saying that manufacturers always claim in brochures and other materials that their products are developed to be super great and specifically for this purpose. This is something they can advertise and make money from."
From this perspective, I find the link to be a refreshing change, and I can't find any absolute deal-breakers from a technical standpoint.

Best regards,

The basic principle is the same, but with a diesel catalytic converter, effectiveness at low temperatures is particularly important, while with a gasoline catalytic converter, it must also be able to withstand higher temperatures if necessary.
However, what's more important is whether they are actually effective. Not like the recalled DPFs.

christians wrote:

The basic principle is the same, however, with a diesel catalytic converter, effectiveness at low temperatures is particularly important, while with a gasoline catalytic converter, it must also be able to withstand higher temperatures if necessary. More importantly, it would be crucial to know whether they are actually effective. Not like the recalled DPFs.

Yawn.


There is no difference between a gasoline and a diesel catalytic converter. There is a cover for the lambda sensor connection.

The old kilns had a ceramic body, while the new ones only have a metal grid.

Bosal catalytic converters have a General Operating Permit (ABE) and do not need to be registered.

A faulty (but not clogged) catalytic converter in a diesel engine may not be detectable during the emissions test because only the opacity is measured, and not the CO levels, as is the case with gasoline engines.

Dear Markus,

Quote:

More importantly, it would be crucial to know whether they are actually effective. Not like the recalled DPFs.

Quote:

Bosal cats have a General Operating Permit (ABE) and do not need to be registered.

Were the DPFs (not catalytic converters) from Bosal and Walker not the ones that were recalled?
It is allegedly a move by the competition, where they sought a specific part (size, fitment for the vehicle) that wasn't quite right, with the intention of casting doubt on the entire range of aftermarket Diesel Particulate Filters (DPFs) from Bosal/Walker.

Quote:

In diesel engines, only oxidation (of HC and CO) occurs because with an excess of oxygen, reduction (of NOx) simply doesn't work. However, the chemistry is otherwise the same.

Here's my understanding: For the three-way catalytic converter from Otto to function optimally, a lambda value of 1 is required so that all molecules with an exothermic reaction tendency can find a reaction partner. Nitrogen oxides are reduced because they were formed endothermically and are theoretically unstable (meaning they would theoretically decompose even without a catalyst), and there are enough other reactive molecules present to "take back" the oxygen from the oxidized nitrogen.

In a diesel oxidation catalyst (DOC), hydrocarbons (HC) and carbon monoxide (CO) are oxidized due to the particularly high residual oxygen content in the exhaust gas, as they will definitely find a reaction partner (oxygen). The nitrogen atoms, which are already more or less "bound" to oxygen during combustion and form nitrogen oxide molecules, do not decompose in this process because oxygen is readily available.

Conclusion: An Ottokat would only operate optimally with diesel fuel if the diesel engine runs at a lambda value of 1 and exhibits a largely homogeneous combustion process, which is not currently possible based on the state of the art. Furthermore, even in gasoline engines, achieving this level of performance across all operating ranges is challenging.

Please correct me if I misunderstood anything!

You can't detect a faulty diesel catalytic converter during the emissions test, but even if you could, all you would really need is a dummy part.

Sure, here is the translation of the text from German to English:

"Hi,"

vwSchrauber wrote:

Conclusion: An Ottokat would only operate optimally with diesel fuel if the diesel engine runs with a Lambda value of 1 and exhibits a largely homogeneous combustion process, which is not currently possible according to the state of the art, nor is it even achievable in all operating ranges for Otto engines.

I see it this way: an Otto catalytic converter works the same on a diesel engine as a diesel catalytic converter does on a diesel engine. The reason it fundamentally cannot reduce NOx emissions is because, with a Lambda value of 1, a diesel engine would severely restrict the visibility for following traffic:lol:.


Best regards, Uli.

I once inquired at a local parts dealer:

There are universal catalytic converters, and it is definitely possible to distinguish between those designed for gasoline (Otto) engines and those designed for diesel engines.

Furthermore, diesel catalytic converters are said to work wonders on gasoline engines. -allegedly- in some gasoline cars with high mileage and problematic exhaust emissions (often the typical lowered, wider, and stiffer models), a used diesel catalytic converter was installed, and subsequently, the exhaust values during the vehicle inspection were within the permissible range .